The Japanese attempt to conquer the world

In the late 16th century, one of the greatest and most devastating wars in the history of Asia, and an important event in world history, was fought among the three greatest powers of East-Asia, both then and today. The war in question is the Japanese invasion attempt of Korea, fought in two stages from 1592 to 1593 and from 1597 to 1598, where also China fought on the Korean side. It is known as the Imjin War (임진왜란, 壬辰倭亂) in Korea; the Wanli Korean Campaign (萬曆朝鮮戰爭) in China; and Bunroku Keichou no eki (文禄・慶長の役) in Japan. It does not have a commonly accepted name in English, but I will refer to it as the Imjin War here. Although the war is probably fairly well-known in Korea and China, it is virtually absent from Japanese history education, regarded there as little more than a misstep of the Japanese unifier Toyotomi Hideyoshi (豊臣秀吉), and it is largely unknown in other countries. Apart from the sheer scale of the fighting forces and the destruction they caused, the war also had long lasting consequences for all three countries involved, and arguably also for the rest of the world.

China, the greatest power in Asia (and possibly in the world) at the time, were in a suzerain relationship with Korea, China being the «father» and Korea the «son» in accordance with the Confucian ideals of a hierarchical order. That being said, the Korean state was almost completely autonomous, its status as a vassal mostly amounting to giving tribute to China, recognizing its own status as inferior, and much cultural and commercial exchange between the two countries. This relationship had a long history, and the Korean Joseon dynasty (조선, 朝鮮, 1392 – 1897) and the Chinese Ming dynasty (明朝, 1368 – 1644) were relatively close, having both come into existence in the aftermath of the Mongol empire’s (the Chinese Yuan dynasty (元朝, 1271 – 1368)) decline. While China always had uprisings in some parts of the country to put down, or raiding barbarians in their borderlands to fight off, Korea had experienced mostly peace since the Mongol conquest and subsequent 100 years of Mongol rule in the 13th century. Its borders were only to China to the north, and the sea in all other directions, and the only two exceptions to this peaceful period were the Jurchen (여진, 女真) tribes from Manchuria gradually brewing up trouble in the north, and the Wokou pirates (왜구, 倭寇, literally “Japanese pirates”) raiding the coast. In addition, Korea had not experienced any naval invasions since ancient times, and as a consequence its southern defences were weak, and its army was almost entirely reliant on peasant reserves.

Oda Nobunaga (織田信長). Source: Wikipedia

Japan, on the other hand, had experienced anything but peace for more than a hundred years. When the Ashikaga shogunate (足利幕府, also known as the Muromachi shogunate, 室町幕府) lost power over the country in the middle of the 15th century, Japan entered what is called the Warring States period or sengoku jidai (戦国時代) for a hundred years, with constant civil wars among the local warlords. The country was temporarily unified by Oda Nobunaga (織田信長) in the middle of the 16th century, but there continued to be unrest. When Nobunaga was trapped in the burning Honnouji (本能寺) temple in Kyoto during an assassination attempt by the traitor Akechi Mitsuhide (明智光秀) in 1582, he promptly committed seppuku (切腹), and Japan was again thrown into turmoil. His successor, Toyotomi Hideyoshi (豊臣秀吉), managed to force the various warlords into submission again. However, he seems to have realized that having the country filled to the rim with veteran professional soldiers and officers, battle-hardened after a lifetime of fighting and suddenly with no more wars to fight, could in itself be a source of unrest. The hundreds of local warlords, many of whom were not at all content with the state of affairs and only loyal to Hideyoshi under the threat of force, did not improve the stability either. This is, at least, generally recognized as one of the reasons why Hideyoshi decided to send a huge army of samurai and accompanying foot soldiers to invade Korea and beyond in the beginning of the 1590’s. It was not the only one, though. Oda Nobunaga had himself expressed interest in eventually conquering Ming China, basically the entire world as known to the Japanese, and ostensibly Hideyoshi shared his lord’s dream. As more realistic goals were eventually set for later campaigns, however, it is of course possible that he was simply aiming for the conquest of Korea and securing its borders.

Map of Joseon Korea at the time of the invasion.

In any case, despite repeated diplomatic missions sent to Japan to gauge the mood there, the Korean leaders completely failed to anticipate the invasion, until Japanese samurai were literally landed on the Korean south-east coast and already advancing northward. The first Japanese forces counted thousands, and caught the coastal city of Pusan (부산, 釜山) completely by surprise when they loaded off their ships, swords and arquebuses in hand, on the evening of May 23rd, 1592. The local Korean forces were totally overwhelmed, a bridgehead was made at Pusan for new forces to land, and the Japanese army immediately continued northward. They swept through the country, and put down the resistance they met with small losses, all the way to Seoul (서울, then Hanseong (한성, 漢城)), the Korean capital, which they entered on June 10th, the Korean king and his court having already left for Pyongyang (평양, 平壌). The Korean capital taken, the Japanese forces, now counting more than a hundred thousand soldiers, split up. Some turned towards the south-western part of the peninsula where Jeolla province (전라도, 全羅道) was, and the rest northwards, towards Pyongyang or all the way to the Yalu river (압록강, 鴨緑江) and China. The Jeolla expedition met fierce resistance, but the north-going forces advanced quickly. In a couple of months, by August 1592, Japanese forces were already engaging the Jurchen, the “barbarian” people living to the North of the Korean border (interestingly enough, Korean forces apparently joined the fight on the Japanese side (Wikipedia)). The conquest of Korea may have been regarded as largely complete, and the Japanese were preparing to continue into Manchuria and China.

A Japanese samurai sword, katana (刀). Source: Wikipedia.

A Sengoku period arquebus replica in Hikone, Shiga prefecture.

Apart from superior numbers, tactics and experience, the Japanese also used more effective weapons than the Korean army. In addition to the samurai sword and spears, early firearms, arquebuses (火縄銃, hinawajuu), were widely used in combination with the more traditional weapons. The arquebuses had originally been presented to the Japanese by Portuguese traders at the end of the Sengoku-period in the 1540’s, but were soon produced in the hundreds of thousands in Japan. The Koreans had not imported any similar technology from abroad, and were largely reliant on the composite bow; a long-range powerful weapon, but initially ineffective against superior numbers of quickly advancing samurai. The Korean rocket-launcher Hwacha (화차, 火車, literally “fire cart”), capable of firing a hundred fire arrows at the same time, was deployed during the war, and must have been an awesome display. However, its effectiveness during the Japanese invasion is contested.

A Korean arrow launcher, hwacha. Source: Wikipedia.

While civil war had prepared the Japanese well for a land-war, the Koreans were superior on the sea. Having had to fight off pirates along the coast for years, they had an experienced and technologically advanced navy. The Japanese “navy”, by contrast, largely consisted of modified merchant vessels for transporting troops, with little or no naval fighting experience. In the middle of June, less than a month into the invasion, the Japanese fleet suffered a crushing defeat in the battle of Okpo (옥포 해전, 玉浦の戦い) by the hand of Korean Admiral Yi Sun-sin (이순신, 李舜臣), often known in English as Admiral Yi. Admiral Yi became a legendary figure in Korean history, and is portrayed as being vital in almost all the important Korean naval victories. This is also supposed to have been brought on partly by his deployment of the mysterious “Turtle ships” (거북선, 亀甲船), although the scope of their use and efficiency remains largely unknown. In either case, the Korean navy largely managed to block the supply lines between Japan and Korea, the Japanese fleet having few means to answer the Korean ship cannons with. Although the Japanese gradually upgraded their fleet and managed to fit looted Korean cannons on some of their ships, the Korean naval supremacy lasted throughout the war, and is regarded as being an indispensable factor in the eventual Korean victory.

Another such indispensable factor was the Chinese military intervention. Although hesitant to help at first, and the Koreans hesitant to ask for it, by January 1593 the Ming had sent a sizeable force (reportedly 30.000 – 40.000 soldiers) to help their vassal state. The intervention may have simply been an attempt to repel foreigners invading “their” sphere of influence, Korea, but the Chinese may also by now have been aware of the Japanese plans to expand further once the Korean conquest was complete. Though smaller in number than their Korean allies, the Chinese soldiers were better equipped (with gunpowder firearms and siege weapons), and experienced from countless encounters with the Jurchen raiders. The Japanese advance came to a halt, and they were soon pushed southwards. In January Chinese forces took Pyongyang, and by April 1593 the Japanese pulled out of Seoul. The Chinese advance had robbed the Japanese of important sources of food, a big setback since the Korean navy were quite effectively cutting off the supply route from Japan. Given the dire situation, Hideyoshi started peace negotiations with Korea and China, and pulled back his troops to Pusan in exchange for most of the Ming forces pulling back to China. Although the negotiations did not lead to much, the Japanese troops slowly transported back to Japan, and by 1597 almost all Japanese and Chinese forces were out of Korea.

Toyotomi Hideyoshi (豊臣秀吉). Source: Wikipedia

Hideyoshi proposed to China a north-south division of Korea, where the southern part would belong to Japan, but his proposal was not accepted by the Chinese side. As a result, Hideyoshi launched a second invasion fleet, with around the same amount of soldiers as the first, early in 1597. Although he at least caught the Chinese, who had already pulled out all their soldiers from Korea, by surprise, the Korean forces were much better prepared this time over, and the Japanese had limited success. A large expedition was again sent towards Jeolla province, but it failed to conquer it, and the rest of the Japanese forces were largely confined to the south-eastern coastal area for the rest of the war. Ming China sent an even bigger contingent to help this time (perhaps 70.000 soldiers), including ships to help out the Korean navy, who again dominated the waters between Korea and Japan. The Japanese continued their fight until the death of Toyotomi Hideyoshi on September 18th 1598. He is supposed to have given the order to withdraw from Korea on his deathbed.

The Imjin war was unique because it featured huge, centrally controlled regular armies (in the hundreds of thousands) fighting with modern (gunpowder) weapons, in a struggle for territory between Asian states. Although similarly scaled wars had been fought several times in China, these were mostly recognized as civil wars, or engagements with less well-organized “barbarian hordes”. The exception would be the Mongol conquests in the 13th century that led to a new Mongol dynasty in China, the Yuan, who led huge forces in successful campaigns all over Asia and even in Europe. Although it is difficult to assess the number of soldiers engaged in the Imjin war, Japan is estimated to have had up to 200.000 troops stationed at one time in Korea (Most of the numbers in this article are from Wikipedia, and even as ballpark figures they should be regarded with a fair amount of scepticism); China up to 80.000; and Korea several hundred thousand. These numbers are only slightly lower than the number of soldiers participating in the Thirty Years War shortly after in Europe, and Napoleon’s 19th century invasion of Russia. Although I do not know much about the subject, the Japanese invasion was probably one of the largest amphibious invasions in world history, on the same scale as the Mongol invasion attempts of Japan 300 years earlier, and possibly not eclipsed until the landing of the Allies in Gallipoli in the Ottoman Empire during World War 1.

In the entire Imjin war, there were perhaps 250.000 military casualties. The brunt of the destruction, however, was for the Korean civilian population to bear. The hundreds of thousands of Japanese soldiers who were stationed on the Korean peninsula for several years, were cut off from supplies from the Japanese islands, and were forced to rely on the local populace for food. Both the Japanese and the Chinese forces were reported to have been brutal to the Korean locals. In addition, almost all the fighting took place in Korea. In this regard, the war can be compared to the 19th century Japanese invasion of China, where many of the important battles between Japan and China were fought on Korean soil, and the 20th century Korean War, fought largely between the United States and China, entirely on the Korean peninsula. In all three cases, the Korean civilian population suffered, especially in the 16th and 20th century conflicts, but considering the population size the Imjin war can be said to have been even more devastating: Although impossible to estimate with any accuracy, around one million civilians are often thought to have died during the war, from a total population that was probably much less than 10 million. In the 1950s Korean war, around 2 million civilians died, but by now the population had grown to around 30 million. The loss of arable land in 16th century Korea, moreover, led to famines for years to come, and countless cultural and historical artefacts were destroyed.

Although certainly an important event in Korean history, the immediate historical consequences there, apart from the decimated population and huge losses of arable land, are ironically less obvious than in the two other power involved in the war. While the Korean Joseon dynasty managed to survive the war, and stayed in power until the late 19th century, the Chinese Ming dynasty fell some decades later to the Manchurian Jurchen, who established the Qing dynasty (清朝) in 1644. Although the takeover was not directly related to the Imjin war, the Ming state exhausted its resources in both the Korean campaigns and against the Mongols on the other side of its empire, while the Jurchen could amass larger and larger raids farther and farther into the exhausted Manchurian territories of China, until it grew strong enough to enter the capital of Beijing.

Tokugawa Ieyasu (徳川家康). Source: Wikipedia.

The Japanese were themselves already in the middle of a change of central power, but the outcome of the Korean invasion may have had strong influence on the evolution of this change. The Japanese defeat in Korea made the Hideyoshi clan very unpopular in Japan, the participating warlords being reluctant to join in on the effort even at the start of the war. With his death, new unrest ensued, and the next warlord to take control of the country was not one of Hideyoshi’s successors, but Tokugawa Ieyasu (徳川家康), who won a decisive victory at The Battle of Sekigahara (関ヶ原の戦い) in 1600, and finally managed to do what Nobunaga and Hideyoshi had failed to: gather the entire country in one centrally controlled political unit and secure the internal peace. The political and social order that the Tokugawa shogunate (徳川幕府) established in Japan would remain essentially unchanged for 250 years, but it was probably quite different from what Nobunaga and Hideyoshi had had in mind. While the two first unifiers had conducted extensive trade and import of knowledge from abroad, and had ambitions to conquer the known world, Tokugawa became more and more sceptical to foreign influence, and limited trade and prosecuted Christians. By the 1630’s, the Tokugawa shogunate had introduced the sakoku (鎖国), or “closed country”, policy. It meant almost completely ending trade with the outside world, a ban on building ships capable of traversing the ocean, and an end to all foreign conquest ambitions. Although it is impossible to know, it does not seem improbable that some of these decisions were influenced by the complete failure of Hideyoshi’s Korean adventure.

In either case, it seems clear that had Japan been able to secure its Korean conquest, history might have taken a quite different course for all three countries involved. And such a possibility was probably not all that distant. Had the Japanese navy been better equipped and able to supply and reinforce the fighting forces, the initial conquest might have been even more overwhelming, and Korea could perhaps have been secured before the Chinese intervention. Had the Chinese decided to let the Koreans fight for themselves, moreover, Korea would probably have been conquered, and its future would be dependent on the endurance of its guerilla forces. Had the Japanese waited a little longer with the conquest of China itself, the crumbling Ming empire might also have been an easier pick. Of course, such thoughts are pure speculation, but considering the position China and Japan, and to a certain extent Korea, have had in modern world history, the actual and potential consequences of the war are truly momentous.

The Japanese invasions were also the start of the anti-Japanese sentiments in Korea (and in a sense also the anti-Korean sentiments in Japan) that lasts until today. These sentiments were, of course, strengthened with the Japanese incursions and eventual annexation of Korea in the late 19th and early 20th century, which were again partly excused with a wish to finish what Hideyoshi had started 300 years earlier. One of the few visible remains of the Imjin war in Japan, and a subject of contention between Korea and Japan, are the mimidzuka (耳塚), literally “ear mound”, of which there are several in western Japan. Japanese tradition required Japanese soldiers to cut off their enemy’s head and show it to their master; however, logistical difficulties with transporting tens of thousands of Korean heads to Japan led to the practice of cutting off the slain enemy’s ears or, more frequently, nose, pickle them, and send them back to Japan. They were then buried in earth mounds, originally called hanadzuka (鼻塚) or “nose mound”, but later known as mimidzuka. Though less well-known in Japan, movements in Korea have asked for the return to Korea of the noses and ears of tens of thousands of Koreans buried in Japan for 400 years. One such mound in Okayama in western Honshuu, found to contain 20.000 Korean noses, was dug up and sent “back” to Korea, where the remains were cremated. The others still exist, however, and the small mounds of raised earth in various locations in Japan can still remind us of the incredible Japanese ambitions when launching an invasion to conquer the entire Chinese empire, and the devastating effects this had on the Korean population.

The mimidzuka (耳塚) in Kyoto, Japan, a twenty minutes walk east from Kyoto Station.

This summary is based on Kyung Moon Hwang’s “A History of Korea” (Palgrave Macmillan 2010), various Wikipedia articles, and things I have read other places.